How can I go about looking up an obit when I don't know that persons last name.

I'm looking for my great grandmother's obit. I know it sounds odd that I wouldn't know her last name but I was told as a child that my grandfather had a step-father. The only thing I knew of my great grandmother until a few years ago was that we called her "Fa-More" (doubt that's spelled correctly).

I have the app for SS# my grandfather filled out, listing his mother as Margot Holm. I do not know if this was her maiden name or her second husband's last name, or what.

I remember seeing pictures of her funeral when I was about 10/11 (c.1980). I know she lived with my grandparents on Long Island when I was a child, but was never told she died until I found the pictures.

If anyone has any suggestions I'd be truly greatful. My email address is audrinamc@yahoo.com and I also use yahoo messenger with that screen name.

Thanks.
Lisa